The present invention relates to novel skin conditioning compositions which are retentive on skin thereby reducing moisture loss from the skin surface.
Various agents have been used in the treatment of human skin to keep the skin in a smooth and supple condition. Skin has the tendency to dry out when exposed to conditions of low humidity or to extended periods in a detergent solution. From a biochemical standpoint, dryness is a measure of the water content of the skin. Inasmuch as the water content and vapor pressure of the epidermis under normal conditions are higher than those of the surrounding air, water evaporates from the skin surface. The skin becomes dry because of loss of moisture from the surface and the subsequent loss of water from the stratum corneum.
Continuous or prolonged immersion in soap or detergent can contribute to dryness of the stratum corneum in that the surfactant medium promotes dissolution of the stratum corneum lipids or epidermal lipids, and the hydroscoic water-soluble components in the corneum.
To alleviate skin dryness, emollient creams have been recommended for application to the skin. The active ingredients in emollient creams probably increase the state of hydration of the corneous layer of the skin by altering the rate of diffusion of water from the skin layers, the rate of evaporation of water from the stratum corneum lipids or epidermal lipids and the ability of the corneous layer to hold moisture.
A wide variety of materials have been disclosed for alleviating the problems of dry skin. A number of polyalcohols or derivatives such as glycerol and glycerol ethers have been used. Glycerol is frequently used because of its excellent humectant properties. Glycerol ethers such as the monoalkyl ethers have found wide spread commercial utility as base materials for cosmetic compositions.
It has been reported that diglycerol can be used as a moistening agent in cosmetic preparations (Japanese Kokai No. 74 41 545-Chem. Abstr., 81 1974 96335j and Japanese Kokai No. 73 91 231-Chem. Abstr., 80 1974 124594t). An emollient cream is disclosed containing beeswax, stearic acid, polawax, various oils, isopropyl myristate, preservatives, and perfumes.